The freelancing sites are ideal for finding the right person for the job. However if you already have been working with a freelancer for a while, it makes little sense to continue paying ~10% commission to these sites. You can find dedicated software that does the same thing much much better and for the fraction of the cost. Below we have tried to compile all the tool that provide this functionality. The programs are ranked in the order of most to least useful in our opinion

1. Screenshot Monitor

ScreenshotMonitor is probably the most intuitive software of this king on the market with a simple but polished tracking application and a fantastic web interface.

2. TimeDoctor

TimeDoctor has a very good desktop client, but its web interface has significant usability issues. User never gets a complete understanding of time spent without picking up bits and pieces from the reports. It tries to be more about time tracking than screenshot monitoring, but it is not competitive in pure time-tracking environment and probably not the best choice in time-tracking + screenshot monitoring area. Still, one of the most full-featured products in this list. Read complete Time Doctor review.

3. Worksnaps

One of the oldest screenshot monitoring programs with quite a lot of features. But it has really old, non-intuitive client interface. The website was recently updated, however most of the administrative portion of the site remained the same.

4. Hubstaff

Hubstaff is run by great marketing people that promote their site better than anyone else in this group. The product however is so-s0. The client is just a tray icon with limited set of functionality and the website is a virtual copy of oDesk and Worksnaps interfaces.

5. Tahometer

A me-too software from a team in Ukraine. Functionally it appear to do just the same as everybody else. But it seems that the team has much stronger programmers than interface designers, it is not the most intuitive to use